In latest Cydia offerings you can now reap the full benefit of multitasking as intended by Apple. The new jailbreak app called LastApp available via BigBoss repo has made getting back to the previous opened app as simple as a tap.
Once you install the LastApp from Cydia you simply go to the Settings-> Activator settings->In
Application, then select your gesture (like double tap status bar).
Now whenever you’re in an app and want to go back to the last one,
double tap the status bar (or whatever you picked) to switch back to the last app you were using.
Switching to the previous opened app using LastApp is much faster than the official double home tapping and then selecting app from the taskbar.